Trafficking/signaling of P2Y receptors in polarized epithelial cells

极化上皮细胞中 P2Y 受体的运输/信号传导

• 批准号: 7372261
• 负责人: ROBERT A NICHOLAS
• 金额: $ 36.45万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-07-01 至 2011-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7372261
• 关键词: Binding Proteins; C-terminal; Caveolae; Cell model; Cells; Chemosensitization; Class; Complement; Disease; Epithelial; Epithelial Cells; Epithelial Receptor Cell; Funding; GPR105 receptor; Hybrids; Hypertension; Ions; Lipids; Lung diseases; Membrane; Membrane Microdomains; Nucleotides; Play; Property; Protein Binding; Proteins; Proteomics; Receptor Signaling; Regulation; Role; Route; Screening procedure; Signal Transduction; Signaling Molecule; Sorting - Cell Movement; Stroke; Surface; Tail; Water; Work; Yeasts; apical membrane; base; basolateral membrane; caveolin 1; extracellular; insight; intracellular protein transport; monolayer; novel; polarized cell; protein localization location; receptor; response; small hairpin RNA; therapeutic target; trafficking

DESCRIPTION (provided by applicant): Our work over the last funding period has focused on characterization of P2Y receptor targeting in polarized cells. These studies established that seven of the eight known subtypes of P2Y receptors display polarized expression in epithelial cells, with four receptors at the basolateral membrane and three receptors at the apical membrane. We have identified and characterized the sorting signals in five of these receptors, which revealed novel mechanisms by which the receptors achieve polarized expression. These findings will be extended to define the physical and structural properties of the sorting signals in the C-terminal tails of P2Y1, P2Y4 , and P2Y14 receptors. The proteins that bind to P2Y receptor sorting signals and direct their polarized targeting are unknown. We will identify these proteins and define their roles in receptor targeting. Lipid microdomains are implicated in localization of proteins in endothelial and epithelial cells and in the regulation of signaling molecules, including P2Y receptors. We will elucidate the role(s) that lipid rafts and caveolae play in the localization and signaling responses of P2Y receptors and delimit the receptor domain(s) involved in these interactions. Successful completion of these projects will provide major new insights into the mechanistic/structural basis of cell targeting and regulation of signaling activities of a therapeutically important class of receptors in the context of a physiologically relevant cell model. The nucleotide-activated P2Y receptors are proven or potential therapeutic targets for treatment of lung diseases, hypertension, and stroke. In epithelial cells, these receptors are targeted to distinct membrane surfaces, where they regulate ion and water transport across the epithelial monolayer. Although cellular mistargeting of proteins is often associated with disease, the cellular mechanisms for proper protein localization are still not well understood. Our studies will provide novel and important information on the cellular mechanisms of P2Y receptor targeting and the regulation of P2Y receptor signaling activity in epithelial cells.

描述（由申请人提供）： 我们在上一个资助期的工作集中在极化细胞中P2 Y受体靶向的表征上。这些研究确定了八种已知的P2 Y受体亚型中的七种在上皮细胞中显示极化表达，其中四种受体在基底外侧膜上，三种受体在顶膜上。我们已经确定并表征了这些受体中的五种中的分选信号，这揭示了受体实现极化表达的新机制。这些发现将被扩展到定义的物理和结构特性的分选信号的C-末端尾部的P2 Y1，P2 Y 4和P2 Y14受体。与P2 Y受体分选信号结合并指导其极化靶向的蛋白质是未知的。我们将鉴定这些蛋白质并确定它们在受体靶向中的作用。脂质微结构域与内皮和上皮细胞中蛋白质的定位以及信号分子（包括P2 Y受体）的调节有关。我们将阐明脂筏和小窝在P2 Y受体的定位和信号转导反应中的作用，并界定参与这些相互作用的受体结构域。这些项目的成功完成将为细胞靶向的机制/结构基础和生理相关细胞模型背景下一类重要的治疗受体的信号传导活性的调节提供重要的新见解。核苷酸激活的P2 Y受体是治疗肺部疾病、高血压和中风的已证实或潜在的治疗靶点。在上皮细胞中，这些受体靶向不同的膜表面，在那里它们调节离子和水跨上皮单层的运输。虽然蛋白质的细胞错误定位通常与疾病有关，但蛋白质正确定位的细胞机制仍然没有很好地理解。我们的研究将为P2 Y受体靶向的细胞机制和上皮细胞中P2 Y受体信号活性的调节提供新的和重要的信息。